urbit/shrub
1
1
Fork 0
mirror of https://github.com/urbit/shrub.git synced 2024-12-24 03:14:30 +03:00
Code Issues Packages Projects Releases Wiki Activity

newt: change framing to tag byte + 32-bit length

Browse Source
This commit is contained in:
Jōshin 2021-12-11 04:54:06 +00:00
parent 5b27010177
commit 9b6332c359
No known key found for this signature in database
GPG Key ID: A8BE5A9A521639D0
2 changed files with 23 additions and 28 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
pkg/urbit/include/vere/vere.h
View File

@ -67,7 +67,7 @@
u3_mess_type sat_e; // msg type
union { //
struct { // awaiting header:
c3_y len_y[8]; // header bytes
c3_y hed_y[5]; // header bytes
c3_y has_y; // length
} hed_u; //
struct { // awaiting body

49
pkg/urbit/vere/newt.c
View File

@ -2,9 +2,11 @@
**
** implements noun blob messages with trivial framing.
**
** a message is a 64-bit little-endian byte count, followed
** by the indicated number of bytes. the bytes are the
** the +jam of of a noun.
** framing is 5 bytes long. first byte is a version tag; a
** character that should never otherwise appear in a message
** intended for urbit. right now we use 0x9, horizontal tab.
** next 32 bits are little-endian byte count. after that is the
** indicated number of bytes, which are the +jam of a noun.
**
** the implementation is relatively inefficient and could
** lose a few copies, mallocs, etc.
@ -117,15 +119,15 @@ u3_newt_decode(u3_moat* mot_u, c3_y* buf_y, c3_d len_d)
while ( len_d ) {
switch( mes_u->sat_e ) {
// read up to 8 length bytes as needed
// read up to 5 bytes as needed
//
case u3_mess_head: {
c3_y* len_y = mes_u->hed_u.len_y;
c3_y* hed_y = mes_u->hed_u.hed_y;
c3_y has_y = mes_u->hed_u.has_y;
c3_y ned_y = 8 - has_y;
c3_y ned_y = sizeof(mes_u->hed_u.hed_y) - has_y;
c3_y cop_y = c3_min(ned_y, len_d);
memcpy(len_y + has_y, buf_y, cop_y);
memcpy(hed_y + has_y, buf_y, cop_y);
buf_y += cop_y;
len_d -= cop_y;
ned_y -= cop_y;
@ -138,18 +140,14 @@ u3_newt_decode(u3_moat* mot_u, c3_y* buf_y, c3_d len_d)
// length known, allocate message
//
else {
c3_d met_d = (((c3_d)len_y[0]) << 0)
| (((c3_d)len_y[1]) << 8)
| (((c3_d)len_y[2]) << 16)
| (((c3_d)len_y[3]) << 24)
| (((c3_d)len_y[4]) << 32)
| (((c3_d)len_y[5]) << 40)
| (((c3_d)len_y[6]) << 48)
| (((c3_d)len_y[7]) << 56);
c3_d met_d = (((c3_d)hed_y[1]) << 0)
| (((c3_d)hed_y[2]) << 8)
| (((c3_d)hed_y[3]) << 16)
| (((c3_d)hed_y[4]) << 24);
// must be non-zero, only 32 bits supported
// check for version tag and nonzero length
//
if ( !met_d || !(0xFFFFFFFFULL > met_d) ) {
if ( 0x9 != hed_y[0] || !met_d ) {
return c3n;
}
@ -379,7 +377,7 @@ typedef struct _n_req {
uv_write_t wri_u;
u3_mojo* moj_u;
c3_y* buf_y;
c3_y len_y[8];
c3_y hed_y[5];
} n_req;
/* _newt_write_cb(): generic write callback.
@ -438,18 +436,15 @@ u3_newt_send(u3_mojo* moj_u, c3_d len_d, c3_y* byt_y)
// write header
//
req_u->len_y[0] = ( len_d & 0xff);
req_u->len_y[1] = ((len_d >> 8) & 0xff);
req_u->len_y[2] = ((len_d >> 16) & 0xff);
req_u->len_y[3] = ((len_d >> 24) & 0xff);
req_u->len_y[4] = ((len_d >> 32) & 0xff);
req_u->len_y[5] = ((len_d >> 40) & 0xff);
req_u->len_y[6] = ((len_d >> 48) & 0xff);
req_u->len_y[7] = ((len_d >> 56) & 0xff);
req_u->hed_y[0] = 0x9;
req_u->hed_y[1] = ( len_d & 0xff);
req_u->hed_y[2] = ((len_d >> 8) & 0xff);
req_u->hed_y[3] = ((len_d >> 16) & 0xff);
req_u->hed_y[4] = ((len_d >> 24) & 0xff);
{
uv_buf_t buf_u[2] = {
uv_buf_init((c3_c*)req_u->len_y, 8),
uv_buf_init((c3_c*)req_u->hed_y, sizeof(req_u->hed_y)),
uv_buf_init((c3_c*)req_u->buf_y, len_d)
};